From the September 2012 issue of HealthCare Business News magazine


Radio frequency coils receive and collect the signal emitted from the given area on the patient. The signal is then amplified and transferred as an image.

Siemens’ Total imaging matrix (Tim) technology was designed to cut examination time down significantly by integrating a high number of coil elements with a high number of RF channels in a number of ways.


“It accelerates the acquisition times and we can go to an acceleration factor of two, three, four and at times in 3-D imaging, we can go up to six,” says Dhamankar. A parallel acquisition factor, or PAT factor, of two would cut scan times nearly in half; PAT3 would mean one-third scan time. For 3-D techniques, PAT is used in two dimensions so PAT2 times PAT3 equals PAT6. In other words, a six minute scan would be close to 1.25 minutes. There are also newer techniques for acquisition currently under 510(k) review, according to Dhamankar.

Digital coiling on new MRI machines has become standard. This means the RF signals are digitized directly at the patient, in the coil itself. According to Philips, this improves the signal to noise ratio by up to 40 percent, compared with non-digital coils.

“That signal to noise can be used to improve scan time so you can start to accelerate the actual imaging time on a patient,” says Mitchell.

A customer can also build these digital coils into the systems themselves. In terms of patient handling, Mitchell says this improves management “so you can get the patient in and out of the scanner very quickly with minimal cabling up of coils on the patient.”

In combination with reduced scan time, he says productivity and efficiency can improve by up to 30 percent.

OEMs also look at their customer’s total cost of ownership with things like upfront costs, installation fees, and upgrading the system through its entire life cycle. This consideration is good news for digital coil users. The digital coils are channeless, so customers don’t have to buy a specific number of channels and worry about pricey upgrades in the future.

More coil elements normally mean better signal reading and faster parallel imaging. In general, companies strive for higher density coil elements.

Dhamankar says Tim technology can integrate a high number of coil elements with a high number of RF channels. According to Siemens, this can reduce examination times by up to 50 percent.

Doing more with less
As MRI procedure times decrease, procedure rates are increasing.

Historically, MRI has been regarded as the optimal modality for neuroradiological and musculoskeletal imaging, but imaging the whole body has opened up new areas for researchers and clinicians alike.

September 2012 Magazine

Read more stories from the September 2012 issue

International Day of Radiology 2012 Homepage